advice, where can I fill up water tank while on the road?

Campgrounds, rest areas, Major truck stops. Anywhere that is supplied with good drinking water. NOT at dump stations!!! We carry about half tank, usually about 30 gal or so. That is usually good for a day or so. We also carry a number of bottles of water for drinking.

Well, to answer your question....most gas stations will have a water supply. As will almost all campgrounds (even when they don't have full Hook-ups)...unless you are planning to camp at a Wilderness Site without any water.

One of the advantages of filling your tank before you leave.......you know what your water tastes like! Not all water tastes the same, or smells the same, and that may be an issue.

Traveling with a full tank probably won't change much of the mileage....it's gonna be bad no matter what:) Are you really excited because your mileage went from 7.25 to 7.3 mpg? Depending on just how you drive, you can probably make up the difference just by slowing down 5 mph.:B

Have a great trip.

I also recommend traveling with a full tank. You do not show what type of rig you have. But 500# will have a negligible effect on MPG's.

We always travel with a full tank of water as well as propane...you just never know. If 500# is over the top for you, you may want to consider trimming weight elsewhere......